Cosmic Background Radiation
Homepage of the Wilkinson Microwave Anisotropy Probe, a NASA satellite launched in 2001. The goal of WMAP are precision measurements of the cosmic microwave background, the "electromagnetic echo" of the big bang phase of the early universe.
One of the homepages of the BOOMERanG project, a balloon-borne millimeter-wave telescope designed to study the anisotropy in the cosmic microwave background radiation. Includes a project overview, a blog, and data releases.